One crow almost hit gymnast (7)
I believe the answer is:
acrobat
'gymnast' is the definition.
(acrobat is a kind of gymnast)
'one crow almost hit' is the wordplay.
'one' becomes 'a' (a thing is one thing).
'almost' means to remove the last letter (most of the word but not all of it).
'hit' becomes 'bat' (batting is a kind of hitting).
'crow' with its last letter taken off is 'cro'.
'a'+'cro'+'bat'='ACROBAT'
(Other definitions for acrobat that I've seen before include "Gymnastic entertainer" , "Spectacular gymnast" , "performer of risky feats?" , "Performing gymnast" , "One appearing head over heels" .)